#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <unistd.h>

int main(void)
{
    sleep(5);
    printf("child = %d, ppid = %d, pgid = %d\n", getpid(), getppid(), getpgrp());
    printf("hello world\n");
    
    sleep(30);
    return 0;
}

